JP2012058412A - Developing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developing device that suppresses unwanted movement from an opening position or a closing position of a shutter.SOLUTION: A shutter drive member 44 is provided with a rack gear 45 that extends in a direction of movement of a shutter 73. A third transmission gear 94 is engaged with the rack gear 45 to transmit the driving force. The transmission of the driving force allows the shutter 73 to move to an opening position and a closing position. The engagement of the rack gear 45 and the third transmission gear 94 is released when the shutter 73 is at the opening position and the closing position.

Description

  The present invention relates to a developing device provided in an image forming apparatus such as a color printer.

  In an example of the image forming apparatus, a photosensitive drum and a developing device are provided, and a toner box containing toner is attached to a case of the developing device.

  The toner box has, for example, a shape having an arc-shaped peripheral surface. A toner discharge port for discharging the toner toward the developing device is formed on the arc-shaped peripheral surface. A sealing material for preventing toner leakage is provided around the toner discharge port. A shutter for opening and closing the toner discharge port is slidably provided outside the arcuate peripheral surface.

  After the toner box is mounted on the case of the developing device, the shutter is slid to open the toner discharge port. As a result, a toner supply path via the toner discharge port is formed between the toner box and the developing device, and toner is supplied from the toner box to the developing device via the toner supply path.

JP-A-7-225514

  In order to move the shutter between an open position where the toner discharge port is opened and a closed position where the toner discharge port is closed, a gear is formed on the shutter, a drive gear meshing with the gear is provided, and the drive gear drives the shutter gear. A configuration for inputting force can be considered.

  However, in that configuration, the shutter is moved from the open position due to undesired rotation of the drive gear, so that the toner supply from the toner box to the developing device is obstructed, or the shutter is moved from the closed position to move from the toner box. The toner may leak out.

  An object of the present invention is to provide a developing device that can prevent undesired movement of the shutter from an open position or a closed position.

  In order to achieve the above-described object, the present invention provides a developing device, wherein the developing unit is configured to be detachable from the developing unit, and an opening for supplying toner contained therein to the developing unit. A toner cartridge having a housing formed with a shutter, and a shutter movably provided in an open position for opening the opening and a closing position for closing the opening; and a first gear extending in the moving direction of the shutter. A shutter driving member coupled to the shutter in a state in which the toner cartridge is mounted on the developing unit, and meshed with the first gear; and the first gear. A second gear for transmitting a driving force to the first gear and the second gear is disengaged when the shutter is in the open position and / or the closed position. It is characterized in.

  According to the present invention, the toner cartridge is configured to be detachable from the developing unit. Further, the toner cartridge includes a housing that accommodates toner therein. An opening for supplying toner to the developing unit is formed in the housing. A shutter is provided to open and close this opening. That is, the shutter is movably provided between an open position that opens the opening and a closed position that closes the opening.

  Further, the developing device is provided with a shutter driving member. With the toner cartridge mounted on the developing unit, the shutter driving member is coupled to the shutter, so that the shutter and the shutter driving member can move together. The shutter driving member is provided with a first gear extending in the moving direction of the shutter. The first gear meshes with the second gear, and the driving force is transmitted from the second gear. The transmission of this driving force moves the shutter to the open position and the closed position.

  When the shutter is located at the open position and / or the closed position, the meshing between the first gear and the second gear is released. Therefore, even if an undesired driving force is input to the second gear, the driving force is not transmitted to the first gear. Therefore, undesired movement from the open position and / or the closed position of the shutter can be prevented.

FIG. 1 is a cross-sectional view of a color printer provided with a developing device according to an embodiment of the present invention. FIG. 2 is a perspective view of the color printer shown in FIG. 1 and shows a state where the drawer unit is located at the drawer position. 3 is a cross-sectional view of the drawer unit shown in FIG. 2 as viewed from the left side and a left side view of the operation member. All the toner cartridges are mounted, and the two rear operation members are in the first posture. The front two operating members show a state of making the second posture. 4 is a cross-sectional view of the drawer unit shown in FIG. 2 as viewed from the right side, showing a state in which all the toner cartridges are detached and all the operation members are in the first posture. FIG. 5 is an exploded perspective view of the toner cartridge shown in FIG. 6A is a cross-sectional view of a main part of the drawer unit shown in FIG. 3 and a left side view of the operation member, showing a state in which the operation member assumes a first posture. FIG. 6B is a cross-sectional view of a main part of the drawer unit shown in FIG. 3 and a left side view of the operation member, showing a state before the operation member takes the second posture. FIG. 6C is a cross-sectional view of the main part of the drawer unit shown in FIG. 3 and a left side view of the operation member, showing a state where the operation member takes the second posture. FIG. 6D is a cross-sectional view of a main part of the drawer unit shown in FIG. 3 and a left side view of the operation member, showing a state before the operation member takes the first posture. FIG. 7 is a side view of a toner cartridge according to Modification 1 (an embodiment in which the return member is provided in the toner cartridge). FIG. 8 is a cross-sectional view of the main parts of the toner cartridge and drawer unit shown in FIG. FIG. 9 is a cross-sectional view of a drawer unit according to Modification 2 (an embodiment in which the return member is made of sponge). FIG. 10 is a cross-sectional view of a drawer unit according to Modification 3 (an embodiment in which the return member is made of a magnet).

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
1. Color Printer As shown in FIG. 1, the color printer 1 is a tandem type color printer. The color printer 1 includes a main body casing 2 as shown in FIGS. A drawer unit 3 is mounted in the main casing 2. A front cover 4 is provided on the front surface of the main casing 2 so as to be openable and closable. The drawer unit 3 is located between the housing position (position shown in FIG. 1) in the main casing 2 and the drawing position (position shown in FIG. 2) outside the main casing 2 with the front cover 4 opened. Can be moved horizontally.

  The side on which the front cover 4 is provided (the right side in FIG. 1) is the front side (front side) of the color printer 1. Then, when the color printer 1 is viewed from the front, the top, bottom, left and right of the color printer 1 are defined. The drawer unit 3 and the toner cartridge 11 attached to the drawer unit 3 define the front, rear, top, bottom, left and right of the drawer unit 3 and the toner cartridge 11 attached to the main body casing 2. In FIG. 2, illustration of the front cover 4 is omitted.

  As shown in FIG. 1, four photosensitive drums 5 are held in the drawer unit 3 so as to be rotatable about rotation axes extending in the left-right direction. The four photosensitive drums 5 are provided for the respective colors of black, yellow, magenta, and cyan, and are arranged in parallel at equal intervals in the front-rear direction in the order of black, yellow, magenta, and cyan from the front side.

  The drawer unit 3 holds four chargers 6. The four chargers 6 are provided corresponding to the photosensitive drums 5, respectively, and are disposed on the rear upper side of the corresponding photosensitive drums 5. The charger 6 is, for example, a scorotron charger having a wire and a grid.

  Furthermore, four developing units 7 are held in the drawer unit 3. The four developing units 7 are provided corresponding to the photosensitive drums 5, respectively, and are disposed on the front upper side of the corresponding photosensitive drums 5.

  Each developing unit 7 includes a developing frame 8. A developing roller 9 and a supply roller 10 are held on the developing frame 8.

  The developing roller 9 is provided so as to be rotatable about a rotation axis extending in the left-right direction, and is disposed so as to contact the photosensitive drum 5.

  The supply roller 10 is provided so as to be rotatable about a rotation axis extending in the left-right direction, and is disposed so as to contact the developing roller 9 from the front upper side.

  In the drawer unit 3, a space 12 for mounting a toner cartridge 11 that contains toner is provided above each developing unit 7. The toner cartridge 11 is mounted in a space 12 above each developing unit 7 from above the drawer unit 3 in a state where the drawer unit 3 is pulled out to the drawing position. Toner is supplied from the toner cartridge 11 to the developing unit 7.

  In the main casing 2, an exposure unit 13 that emits four laser beams corresponding to each color is disposed above the drawer unit 3.

  As the photosensitive drum 5 rotates, the surface of the photosensitive drum 5 is uniformly charged by the discharge from the charger 6 and then selectively exposed by the laser beam from the exposure unit 13. By this exposure, electric charges are selectively removed from the surface of the photosensitive drum 5, and an electrostatic latent image is formed on the surface of the photosensitive drum 5. When the electrostatic latent image faces the developing roller 9, toner is supplied from the developing roller 9 to the electrostatic latent image. As a result, a toner image is formed on the surface of the photosensitive drum 5.

  Instead of the exposure device 13, four LED arrays may be provided corresponding to each photosensitive drum 5.

  At the bottom of the main casing 2, a paper feed cassette 14 that stores paper P is disposed. The paper P stored in the paper feed cassette 14 is transported onto the transport belt 15 by various rollers. The conveyor belt 15 is disposed facing the four photosensitive drums 5 from below. A transfer roller 16 is disposed at each position facing the photosensitive drum 5 with the upper portion of the conveyance belt 15 interposed therebetween. The paper P transported on the transport belt 15 sequentially passes between the transport belt 15 and each photosensitive drum 5 as the transport belt 15 travels. The toner image on the surface of the photosensitive drum 5 is transferred to the paper P when facing the paper P.

A fixing device 17 is provided on the downstream side in the conveyance direction of the paper P with respect to the conveyance belt 15. The paper P on which the toner image is transferred is conveyed to the fixing device 17. In the fixing device 17, the toner image is fixed on the paper P by heating and pressing. The paper P on which the toner image is fixed is discharged to a paper discharge tray 18 on the upper surface of the main casing 2 by various rollers.
2. Drawer Unit (1) Drawer Frame As shown in FIG. 2, the drawer unit 3 includes a drawer frame 31. The drawer frame 31 includes a pair of side plates 32 and 33 facing each other at an interval in the left-right direction, a front beam 34 laid between the front end portions of the side plates 32 and 33, and the rear end portions of the side plates 32 and 33. A rear beam 35 is provided between them, and as a whole has a square frame shape in plan view.

The four photosensitive drums 5, the four chargers 6, and the four developing units 7 (see FIG. 1) are collectively held by the side plates 32 and 33 while being sandwiched from the left and right sides. Between the side plates 32 and 33, a space 12 for mounting the toner cartridge 11 is provided above each developing unit 7. In other words, the side plates 32 and 33 hold the four photosensitive drums 5, the charger 6, and the developing unit 7, and leave a space 12 for mounting the toner cartridge 11 in the left and right direction, Facing each other in the direction.
(2) Development Frame As shown in FIGS. 2 and 3, the development frame 8 is arranged at equal intervals in the front-rear direction and is laid between the side plates 32 and 33. Each space 12 for mounting the toner cartridge 11 is divided by the developing frame 8.

  As shown in FIG. 3, the developing frame 8 is formed with a developing chamber 41 that houses the developing roller 9. The developing chamber 41 is open on the photosensitive drum 5 side, and the developing roller 9 is disposed at the open end of the developing chamber 41.

  The developing frame 8 has a plate-shaped partition wall 42 that is convexly curved in an arc shape toward the developing chamber 41 side between the developing chamber 41 and the space 12 for mounting the toner cartridge 11. The partition wall 42 partitions the developing frame 8 into a developing chamber 41 and a space 12 above the developing chamber 41. At the center of the partition wall 42 in the circumferential direction, in a state where the toner cartridge 11 is mounted in the space 12, at a position facing the three communication ports 58 (see FIG. 5) formed in the toner cartridge 11. Three rectangular openings 43 are formed.

2 shows a state in which only one toner cartridge 11 is held by the drawer frame 3, and the other three toner cartridges 11 are not shown.
(3) Shutter driving member Above the partition wall 42, a shutter driving member 44 for driving a shutter 73 described later is movably disposed.

The shutter drive member 44 has a plate shape that is convexly curved in an arc shape toward the developing chamber 41 so as to substantially follow the partition wall 42. A rack gear 45 as an example of a first gear is formed on the lower surface of the shutter driving member 44. As shown in FIG. 2, shutter driving protrusions 46 are formed on the upper surface of the shutter driving member 44 at positions corresponding to shutter driving openings 88 described later.
(4) Operation member An operation member 101 is provided at the left end of each space 12. The operation member 101 integrally includes a rectangular plate-shaped restricting portion 102 and a drive gear portion 103 that is connected to the restricting portion 102 and is an example of a substantially ¼ fan-shaped missing tooth gear in a side view. . The operation member 101 is provided so as to be displaceable between a first posture in which the restricting portion 102 protrudes and extends above the drawer frame 31 and a second posture in which the restricting portion 102 extends along the upper end surface of the drawer frame 31. ing.

  Hereinafter, the description of the configuration of the operation member 101 is based on the state in which the operation member 101 is in the first posture.

  The drive gear portion 103 is formed such that a portion having one radius of the fan shape is connected to the restricting portion 102 and a portion forming the fan-shaped arc bulges forward and upward. As shown in FIG. 3, a swing shaft 104 extending in the left-right direction is rotatably inserted into the drive gear portion 103 near the center of the fan shape. The left end portion of the swing shaft 104 is supported by the left side plate 32 so as not to be relatively rotatable. Accordingly, the operation member 101 is supported by the side plate 32 via the swing shaft 104 so as to be swingable. The operation member 101 can be displaced between the first posture and the second posture by swinging with the swing shaft 104 as a fulcrum.

  A large number of gear teeth 105 are formed in the lower half portion of the drive gear portion 103 that forms a fan-shaped arc.

As shown in FIG. 4, a guide groove 106 is formed on the right side surface of the drive gear portion 103. The guide groove 106 is opened at the upper half of the fan-shaped arc, extends downward, bends rearwardly, and extends to a portion through which the swing shaft 104 is inserted. Further, the drive gear portion 103 is formed with an inclined guide surface 107 that is inclined rearwardly (forwardly downward) between the upper end of the guide groove 106 and the inner surface of the restricting portion 102.
(5) Holding Structure As shown in FIG. 2, a concave portion 108 having a rectangular shape in plan view is formed on the upper end surface of the left side wall 32 corresponding to the restricting portion 102. The depth of the recess 108 is substantially the same as the thickness of the restricting portion 102. Further, as shown in FIG. 2, a left front end portion of an upper surface 52 of a casing 51 (described later) of the toner cartridge 11 is opened to the left and front in a rectangular shape in plan view corresponding to the restriction portion 102. A recess 109 is formed. When the operation 101 is in the second posture, the restricting portion 102 is fitted into the recesses 108 and 109, the lower surface of the restricting portion 102 contacts the upper end surface of the side wall 32 in the recess 108, and the upper surface of the restricting portion 102 is the housing. 51 is substantially flush with the upper surface 52 of 51 and the upper end surfaces of the side walls 32, 33.

In addition, on the inner side surface (left side surface) of the right side plate 33, support grooves 110 and 111 are formed in the front-rear direction so as to be spaced apart from each other, corresponding to each space 12. The support grooves 110 and 111 extend in the vertical direction and are opened upward. Further, the upper end portions of the support grooves 110 and 111 expand toward the upper side, and the support grooves 110 and 111 have a substantially Y shape in a side view. The front support groove 110 is longer than the rear support groove 111 in the vertical direction.
3. Toner Cartridge (1) Housing As shown in FIG. 5, the toner cartridge 11 includes a resin housing 51 that accommodates toner therein. The housing | casing 51 is formed in the hollow substantially semicircular column shape extended in the left-right direction. Specifically, the housing 51 has a space for accommodating toner therein, is connected to the substantially rectangular upper surface 52 that is long on the left and right, and the front edge of the upper surface 52, and has a cross-sectional shape that is convexly curved downward. A semicircular arc-shaped arc surface 53, a fixed surface 54 extending in parallel with the upper surface 52 from the rear end edge of the arc surface 53 to the rear, and a rear end edge of the upper surface 52 and a rear end edge of the fixed surface 54 are straddled. The rear surface 55, the upper surface 52, the arc surface 53, the left surface 56 straddling the left end edges of the fixing surface 54 and the rear surface 55, and the right end edges of the upper surface 52, the arc surface 53, the fixing surface 54 and the rear surface 55. And a right side surface 57 straddling it.

  The arc surface 53 is formed with a communication port 58 as an example of three openings that communicate the inside and outside of the housing 51 at a portion slightly behind the lowermost end. The three communication ports 58 are formed side by side in the left-right direction and have a rectangular shape that is long in the left-right direction.

  In addition, on the arc surface 53, elongated groove-like escape grooves 59 extending in the circumferential direction of the arc surface 53 are formed on the left and right sides of each communication port 58.

  As shown in FIG. 3, a plurality of positioning projections 60 are formed at the front end portion of the arc surface 53 at intervals in the left-right direction. Each positioning projection 60 has a hook shape extending forward, bent and extending upward.

  As shown in FIG. 5, a columnar boss 61 projects from the left side surface 56 at the center of the portion surrounded by the periphery of the arc surface 53. A driven gear 62 is rotatably held by the boss 61. Further, a columnar support protrusion 63 projects from the rear upper end portion of the left side surface 56.

  In FIG. 5, the driven gear 62 is not shown.

  A columnar support protrusion 64 projects from the rear upper end of the right side surface 57. Further, on the right side surface 57, although not shown, a columnar support protrusion projects from the center of the portion surrounded by the periphery of the arc surface 53.

The toner cartridge 11 includes a toner seal 71 attached to the arc surface 53 of the housing 51, a shutter cover 72 provided so as to cover the arc surface 53, and a shutter provided between the arc surface 53 and the shutter cover 72. 73.
(2) Toner Seal The toner seal 71 is provided corresponding to each communication port 58. The toner seal 71 is formed in a sheet shape having an opening 74 corresponding to the communication port 58. The toner seal 71 is aligned so that the communication port 58 and the opening 74 are in communication with each other so as to face each other, and is adhered to the arc surface 53 of the casing 51 so as to surround the communication port 58.
(3) Shutter Cover The shutter cover 72 is made of a resin film and is curved along the arc surface 53 of the casing 51. The width in the left-right direction of the shutter cover 72 is substantially equal to the width in the left-right direction of the arc surface 53, and the shutter cover 72 covers the arc surface 53 over almost the entire width in the left-right direction.

  A plurality of positioning openings 80 are formed at the front end portion of the shutter cover 72 at intervals in the left-right direction. Each positioning opening 80 is engaged with a positioning protrusion 60 (see FIG. 3) formed on the arc surface 53 of the housing 51. More specifically, a positioning opening 80 having a size capable of inserting the positioning protrusion 60 is formed at the front end of the shutter cover 72 at the same position in the left-right direction as each positioning protrusion 60. A positioning projection 60 is inserted into each positioning opening 80, and an upper end edge of the positioning projection 60 is locked to the positioning projection 60.

  Further, the rear end portion of the shutter cover 72 is bent along the fixed surface 54 of the housing 51. A plurality of screw insertion holes 81 are formed in the rear end portion of the shutter cover 72 at intervals in the left-right direction. Then, each positioning opening 80 and the positioning projection 60 are engaged, and a screw 82 (see FIG. 3) is inserted into each screw insertion hole 81, and the tip of each screw 82 is the fixing surface 54 of the housing 51. The shutter cover 72 is attached to the casing 51 by being screwed into the casing 51.

  Further, the toner cover opening 83 is formed in the shutter cover 72 at a position facing each toner seal 71. The toner circulation opening 83 has a rectangular shape that is long in the left-right direction, and has an opening area larger than the opening area of the communication port 58 and is formed so as to expose the entire area of the communication port 58.

Further, the shutter cover 72 is formed with guide openings 85 extending in the front-rear direction (the circumferential direction of the shutter cover 72) at positions facing the respective escape grooves 59 of the housing 51. The length of the guide opening 85 in the front-rear direction is equal to or longer than the length of the escape groove 59 in the front-rear direction. The width of the guide opening 85 in the left-right direction is equal to or greater than the width of the escape groove 59 in the left-right direction. The guide opening 85 faces the entire escape groove 59.
(4) Shutter The shutter 73 is made of a resin film and is curved along the arc surface 53 of the casing 51. The width of the shutter 73 in the left-right direction is slightly smaller than the width of the shutter cover 72 in the left-right direction. The shutter 73 is larger in the direction along the circular arc surface 53 than the width of the toner seal 71 in the direction along the circular arc surface 53, and when the shutter 73 is moved between an open position and a closed position described later. The shutter 73 has such a width that it does not come into contact with the fixed surface 54 of the housing 51 and the positioning projection 60.

  In the shutter 73, two shutter driving openings 88 are formed at positions facing the respective escape grooves 59 of the housing 51 with an interval in the circumferential direction of the shutter 73. Whether the shutter 73 is in the open position or the closed position, all the shutter driving openings 88 face the escape groove 59 and communicate with the guide opening 85 of the shutter cover 72. In addition, the interval between the two shutter driving openings 88 at each position is determined.

  The shutter 73 is sandwiched between the arcuate surface 53 of the housing 51 and the shutter cover 72 and is moved between the open position and the closed position while being held by them.

  In the open position, the rear end portion of the shutter 73 is sandwiched between the front end portion of the toner seal 71 and the shutter cover 72. Therefore, the communication port 58 of the housing 51 and the opening 74 of the toner seal 71 are opened in a state where they communicate with each other, and the inside and outside of the housing 51 communicate with each other.

On the other hand, the closed position is a rear position with respect to the open position. In the closed position, the rear end edge of the shutter 73 is positioned slightly behind the rear end edge of the toner circulation opening 83. Therefore, the entire area of the communication port 58 of the casing 51 and the opening 74 of the toner seal 71 are covered by the shutter 73, and the inside and outside of the casing 51 are blocked by the shutter 73. At this time, the toner seal 71 is sandwiched between the shutter 73 and the arcuate surface 53 of the housing 51.
4). Drive transmission mechanism A drive transmission mechanism 91 for transmitting the rotation of the driven gear 62 provided in the toner cartridge 11 to the rack gear 45 of the shutter drive member 44 corresponding to each shutter drive member 44 in the drawer frame 31. Is provided. As shown in FIG. 6A, the drive transmission mechanism 91 includes a first transmission gear 92 that meshes with the driven gear 62 in a state where the toner cartridge 11 is mounted in the space 12, and a second mesh that meshes with the first transmission gear 92. A transmission gear 93 and a third transmission gear 94 as an example of a second gear meshing with the second transmission gear 93 and the rack gear 45 are provided. The first transmission gear 92, the second transmission gear 93, and the third transmission gear 94 are rotatably held on the left side plate 32 of the drawer frame 31.

When the driven gear 62 is rotated, a rotational force is applied from the driven gear 62 to the first transmission gear 92, and the first transmission gear 92 rotates. The rotational force applied to the first transmission gear 92 is transmitted to the rack gear 45 via the second transmission gear 93 and the third transmission gear 94. As a result, the shutter driving member 44 moves in the front-rear direction along the partition wall 42, and the shutter 73 moves between the open position and the closed position together with the shutter driving member 44 as described below. Therefore, the driven gear 62, the first transmission gear 92, the second transmission gear 93, the third transmission gear 94, and the rack gear 45 constitute a drive mechanism (gear train) for moving the shutter 73 from the open position to the closed position. is doing.
5. Returning member The developing frame 8 is provided with a block-shaped spring holding portion 121 at a position spaced above the front end portion of the shutter driving member 44 disposed at a position corresponding to the opening position of the shutter 73. ing. One end of the first return member 122 made of a coil spring is held by the spring holding portion 121. The first return member 122 extends downward from the spring holding portion 121.

  Further, the developing frame 8 has a block-shaped spring holding portion at a position spaced along the partition wall 42 with respect to the rear end portion of the shutter driving member disposed at a position corresponding to the closed position. 123 is provided. One end of a second return member 124 made of a coil spring is held by the spring holding portion 123. The second return member 124 extends forward and downward from the spring holding portion 123.

The developing unit 7, the toner cartridge 11, the shutter driving member 44, the driven gear 62, the first transmission gear 92, the second transmission gear 93, the third transmission gear 94, the first return member 122, and the second return member 124 are An example of the developing device is configured.
6). Attaching / Removing Toner Cartridge (1) Attaching Toner Cartridge As shown in FIG. 2, the toner cartridge 11 has a drawer frame 31 in a state where the drawer unit 3 (drawer frame 31) is pulled out of the main body casing 2. It is attached to and detached from each space 12 from above. The mounting of the toner cartridge 11 in the space 12 can be considered as mounting of the toner cartridge 11 in the developing unit 7.

  With the toner cartridge 11 detached from the drawer unit 3, the shutter 73 is located at the closed position.

  When the toner cartridge 11 is mounted in the space 12, as shown in FIG. 6A, the operation member 101 corresponding to the space 12 is in the first posture. Then, the support protrusion 63 protruding from the left side surface 56 of the housing 51 is inserted into the guide groove 106 (see FIG. 4) of the operation member 101 from above. Further, a support protrusion (not shown) and a support protrusion 64 (see FIG. 5) that are provided on the right side surface 57 of the housing 51 are inserted into the support grooves 110 and 111 of the side plate 33 from above.

  At this time, the support protrusion 63 is guided to the guide groove 106 by being moved along the inner surface of the restricting portion 102 and the inclined guide surface 107. With this guidance, a support protrusion and a support protrusion 64 (not shown) on the right side surface 57 are guided to the support grooves 110 and 111, respectively. The support protrusion 63 moves downward while being guided by the guide groove 106, and the support protrusion and the support protrusion 64 (not shown) move downward in the support grooves 110 and 111, respectively. When the support protrusion 63 reaches the deepest portion of the guide groove 106 and the support protrusion and the support protrusion 64 (not shown) reach the deepest portions of the support grooves 110 and 111, the toner cartridge 11 is mounted in the space 12. As a result, the toner cartridge 11 is supported by the drawer frame 31.

  In this state, the shutter driving protrusions 46 are engaged with the shutter driving openings 88 through the guide openings 85, and the shutter 73 and the shutter driving member 44 are coupled. Further, as shown in FIG. 6A, the driven gear 62 of the toner cartridge 11 is engaged with the first transmission gear 92. The gear teeth 105 of the operation member 101 are disposed above the driven gear 62 and do not mesh with the driven gear 62. The rack gear 45 and the third transmission gear 94 are not meshed with each other, and the foremost gear teeth of the rack gear 45 and the gear teeth of the third transmission gear 94 are in contact with each other.

  Thereafter, the operation member 101 is displaced from the first posture to the second posture. As the operating member 101 is displaced, the gear teeth 105 rotate clockwise as viewed from the left side. In the middle of this rotation, as shown in FIG. 6B, the gear teeth 105 mesh with the driven gear 62, and the rotation of the gear teeth 105 after the meshing causes the driven gear 62 to rotate counterclockwise as viewed from the left side. Rotate to. A rotational force is generated from the driven gear 62 by the rotation of the driven gear 62. This rotational force is transmitted to the third transmission gear 94 via the first transmission gear 92 and the second transmission gear 93, and the third transmission gear 94 rotates clockwise as viewed from the left side. As the third transmission gear 94 rotates, the rack gear 45 and the third transmission gear 94 mesh with each other, and the shutter driving member 44 moves forward from a position facing the opening 43 to a position not facing the opening 43. As the shutter drive member 44 moves, the shutter 73 moves forward from the closed position to the open position integrally with the shutter drive member 44.

  The gear teeth 105 are engaged with the driven gear 62, and the front end portion of the shutter driving member 44 contacts the first return member 122 before the shutter 73 reaches the open position. After the shutter drive member 44 abuts on the first return member 122, the shutter drive member 44 is further moved, so that the first return member 122 is compressed as shown in FIG. 6B. As a result, the shutter drive member 44 receives an urging force from the first return member 122 in a direction in which the shutter 73 moves from the open position to the closed position, and the urging force from the first return member 122 gradually increases with the movement. Strengthen. Then, the shutter 73 moves to a position beyond the open position, the meshing between the rack gear 45 and the third transmission gear 94 is released, and the rearmost gear teeth of the rack gear 45 are arranged in front of the third transmission gear 94. .

  When the operation member 101 is in the second posture, the restricting portion 102 faces the toner cartridge 11 from above. For this reason, the toner cartridge 11 cannot be extracted from the drawer frame 31. Further, as shown in FIG. 6C, the meshing between the driven gear 62 and the gear teeth 105 is released, and the gear teeth 105 are arranged behind the driven gear 62. The shutter 73 that has moved to a position beyond the open position immediately before the operating member 101 takes the second posture is returned to the open position together with the shutter drive member 44 by the biasing force received by the shutter drive member 44 from the first return member 122. . When the operation member 101 is in the second posture, the rearmost gear teeth of the rack gear 45 abut on the gear teeth of the third transmission gear 94 from the front side.

Thereafter, when the front cover 4 (see FIG. 1) is closed, the image forming operation in the color printer 1 can be started.
(2) Removal of Toner Cartridge When the toner cartridge 11 is removed from the drawer unit 3, the front cover 4 is opened and the drawer unit 3 is pulled out from the storage position to the pull-out position. Then, the operation member 101 is displaced from the second posture shown in FIG. 6C to the first posture shown in FIG. 6A.

  As the operating member 101 is displaced, the gear teeth 105 rotate counterclockwise as viewed from the left side. In the middle of this rotation, as shown in FIG. 6D, the gear teeth 105 mesh with the driven gear 62, and the rotation of the gear teeth 105 after the meshing causes the driven gear 62 to rotate clockwise as viewed from the left side. Rotate. A rotational force is generated from the driven gear 62 by the rotation of the driven gear 62. This rotational force is transmitted to the third transmission gear 94 via the first transmission gear 92 and the second transmission gear 93, and the third transmission gear 94 rotates counterclockwise as viewed from the left side. As the third transmission gear 94 rotates, the rack gear 45 and the third transmission gear 94 mesh with each other, and the shutter driving member 44 moves backward from a position not facing the opening 43 to a position facing the opening 43. As the shutter drive member 44 moves, the shutter 73 moves backward from the open position toward the closed position integrally with the shutter drive member 44.

  The gear teeth 105 mesh with the driven gear 62, and the front end of the shutter driving member 44 contacts the second return member 124 before the shutter 73 reaches the closed position. After the shutter drive member 44 comes into contact with the second return member 124, the shutter drive member 44 is further moved, whereby the second return member 124 is compressed as shown in FIG. 6D. As a result, the shutter drive member 44 receives an urging force from the second return member 124 in the direction in which the shutter 73 moves from the closed position to the open position, and the urging force from the second return member 124 gradually increases with the movement. Strengthen. Then, the shutter 73 moves to a position that once exceeds the closed position, the meshing between the rack gear 45 and the third transmission gear 94 is released, and the foremost gear teeth of the rack gear 45 are arranged behind the third transmission gear 94. .

  When the operation member 101 is in the second posture, as shown in FIG. 6A, the meshing between the driven gear 62 and the gear teeth 105 is released, and the gear teeth 105 are arranged above the driven gear 62. The The shutter 73 that has moved to a position beyond the closing position immediately before the operation member 101 takes the second posture is returned to the closing position together with the shutter driving member 44 by the biasing force received by the shutter driving member 44 from the second return member 124. . When the operation member 101 is in the first posture, the foremost gear teeth of the rack gear 45 abut on the gear teeth of the third transmission gear 94 from the rear side.

Thereafter, the toner cartridge 11 is pulled upward from the space 12. When the toner cartridge 11 is detached from the drawer unit 3, the shutter 73 is disposed at the closed position, so that there is no possibility that toner will spill out from the housing 51 of the toner cartridge 11 that has been taken out.
7). Function and Effect (1) Function and Effect 1
As described above, the toner cartridge 11 is configured to be detachable from the developing unit 7. In addition, the toner cartridge 11 includes a housing 51 that stores toner therein. A communication port 58 for supplying toner to the developing unit 7 is formed in the housing 51. A shutter 73 is provided to open and close the communication port 58. That is, the shutter 73 is provided to be movable between an open position where the communication port 58 is opened and a closed position where the communication port 58 is closed.

  A shutter drive member 44 is provided on the development frame 8. In a state where the toner cartridge 11 is mounted on the developing unit 7, the shutter driving member 44 is coupled to the shutter 73, and the shutter 73 and the shutter driving member 44 can move integrally. The shutter drive member 44 is provided with a rack gear 45 extending in the moving direction of the shutter 73. The rack gear 45 is engaged with the third transmission gear 94, and the driving force is transmitted from the third transmission gear 94. By transmitting this driving force, the shutter 73 is moved between the open position and the closed position.

When the shutter 73 is in the open position and the closed position, the meshing between the rack gear 45 and the third transmission gear 94 is released. Therefore, even if an undesired driving force is input to the third transmission gear 94, the driving force is not transmitted to the rack gear 45. Therefore, undesired movement of the shutter 73 from the open position and the closed position can be prevented.
(2) Action effect 2
In addition, a first return member 122 and a second return member 124 are provided. When the shutter 73 is located at the open position and the closed position, the first return member 122 and the second return member 124 urge the shutter drive member 44, respectively, and thereby the meshing with the third transmission gear 94 is performed. The released teeth of the rack gear 45 abut on the teeth of the third transmission gear 94. Therefore, when the driving force is input to the third transmission gear 94 to move the shutter 73 from the open position or the closed position, the rack gear 45 and the third transmission gear 94 mesh with each other at the timing when the third transmission gear 94 starts to rotate. To do. As a result, it is possible to prevent variation in the meshing timing between the rack gear 45 and the third transmission gear 94.

If the timing of meshing between the rack gear 45 and the third transmission gear 94 varies, the position of the shutter 73 at the end of the rotation of the third transmission gear 94 varies. Variations in the timing of meshing between the rack gear 45 and the third transmission gear 94 are prevented, so that the position of the shutter 73 can be managed with high accuracy.
(3) Effect 3
The first return member 122 and the second return member 124 drive the shutter when the rack gear 45 and the third transmission gear 94 are engaged with each other before the shutter 73 reaches the open position and the closed position by movement. The biasing of the member 44 is started.
(4) Action effect 4
The drawer frame 31 is provided with a drive gear portion 103 that meshes with the third transmission gear 94 and transmits a driving force input from the outside to the third transmission gear 94. When the shutter 73 is located at the open position and the closed position, the meshing between the third transmission gear 94 and the drive gear portion 103 is released. Here, the concept of meshing between the third transmission gear 94 and the drive gear portion 103 includes not only the case where the third transmission gear 94 and the drive gear portion 103 mesh directly, but also the third transmission gear 94 and the drive gear portion 103. Are engaged (connected) via the driven gear 62, the first transmission gear 92, and the second transmission gear 93. Since the meshing between the third transmission gear 94 and the drive gear portion 103 is released, an undesired driving force is transmitted from the drive gear portion 103 to the third transmission gear 94 when the shutter 73 is located at the open position and the closed position. It will not be done. As a result, undesired movement of the shutter 73 from the open position and / or the closed position can be further prevented.
8). Modification (1) Modification 1
Although the first return member 122 and the second return member 124 are provided in the developing frame 8 of the developing unit 7, they may be provided in the toner cartridge 11 as shown in FIGS. That is, a spring holding portion 121 is provided in a portion of the toner cartridge 11 facing the front side of the circular arc surface 53 of the casing 51, and the upper end of the first return member 122 is connected to the spring holding portion 121, and the second return The upper end of the member 124 may be connected to the fixed surface 54 of the housing 51.
(2) Modification 2
The first return member 122 and the second return member 124 are not limited to coil springs, and may be sponges as shown in FIG.
(3) Modification 3
As shown in FIG. 10, the first return member 122 is configured by a pair of a magnet 131 provided on the developing frame 8 and a magnet 132 provided on the front end portion of the shutter driving member 44, and the developing frame 8 The second return member 124 may be configured by a pair of the magnet 133 provided in the magnet and the magnet 134 provided in the rear end portion of the shutter driving member 44. In this case, magnets 131 and 132 are provided such that the same poles (for example, S poles) face each other, and magnets 133 and 134 are provided so that the same poles (for example, N poles) face each other.
(4) Modification 4
When the shutter 73 is located at the open position and the closed position, the meshing between the rack gear 45 and the third transmission gear 94 is released, but when the shutter 73 is located at at least one of the open position and the closed position, The meshing between the rack gear 45 and the third transmission gear 94 may be released. When the shutter 73 is located in at least one of the open position and the closed position, the meshing between the rack gear 45 and the third transmission gear 94 is released, so that the position of the shutter 73 can be reset to the normal position.

In addition, when the configuration in which the rack gear 45 and the third transmission gear 94 are disengaged when the shutter 73 is located in at least one of the open position and the closed position, the shutter 73 is located in the open position. It is preferable to employ a configuration in which the meshing between the rack gear 45 and the third transmission gear 94 is released.
(5) Modification 5
The present invention is not limited to a tandem type color printer, but can be applied to a color printer other than a tandem type. Further, the present invention can be applied not only to a color printer but also to a monochrome printer.

  In addition, various design changes can be made to the above-described embodiments and modifications within the scope of the matters described in the claims.

7 Developing section 11 Toner cartridge 44 Shutter driving member 45 Rack gear 51 Housing 58 Communication port 94 Third transmission gear 101 Operation member 103 Driving gear section 105 Gear teeth 122 First return member 124 Second return member

Claims (9)

A developing section;
The housing is configured to be detachable from the developing unit, and has a housing formed with an opening for supplying toner contained therein to the developing unit, an open position for opening the opening, and the opening being closed. A toner cartridge having a shutter movably provided at a closing position to be closed;
A shutter driving member having a first gear extending in a moving direction of the shutter, coupled to the shutter in a state where the toner cartridge is mounted on the developing unit, and movable integrally with the shutter;
A second gear that meshes with the first gear and transmits a driving force to the first gear;
The developing device, wherein the engagement between the first gear and the second gear is released when the shutter is located at the open position and / or the closed position.   When the shutter is located at the open position and / or the closed position, the shutter driving member is urged to disengage the first gear teeth that are disengaged from the second gear. The developing device according to claim 1, further comprising a return member that contacts the gear teeth.   The return member is attached to the shutter drive member when the first gear and the second gear are engaged with each other before the shutter reaches the open position and / or the closed position by movement. The developing device according to claim 2, wherein the developing device is started.   The developing device according to claim 2, wherein the return member is provided in the developing unit.   The developing device according to claim 2, wherein the return member is provided in the toner cartridge.   The developing device according to claim 2, wherein the return member is a spring. A chipped gear that meshes with the second gear and transmits a driving force input from the outside to the second gear;
The developing device according to claim 1, wherein when the shutter is located at the open position and the closed position, the meshing between the second gear and the chipped gear is released.   The developing device according to claim 1, wherein the engagement of the first gear and the second gear is released at least when the shutter is located at the open position.   The developing device according to claim 8, wherein when the shutter is located at the open position and the closed position, the meshing between the first gear and the second gear is released.

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